Grinding apparatus



Feb. 5, 1929. l 1,701,456

C. H; SCHURR GRINDING APPARATUS Filed .May l5. 1922 8 Sheets-Sheet l C. H. SCHURR Feb. 5, 1929.

GRINDING APPARATUS Filed May l5. 1922 8 Sheets-Sheet ---w l y 4 @ffm /1/ MMM (l Holz/nocd GRINDTNG APPARATUS Filed May l5. 1922 /r/GZ.

8 Sheets-Sheet 5 /6/6a Feb. 5, 1929.

C. H. SCHURR I @BINDING APPARATUS Filed' May 15, 1922 8 Sheets-Sheet 4 C. H. SCHURR GRINDTNG APPARATUS Filed May l5. 1922 8 Sheets-Sheet 5 c'. H. scHURR Feb. 5, 1929.

GRINDI NG APPARATUS 8 Sheets-Sheet 7 Filed May l5, 1922 Patented Feb. 5, 1m.

UNITED STATES PATENT oFFlcE.

CHARLES H.

SCHUBB, OF CLEVELAND, OHIO, ASSIGNOR T10 THE 'LEES-BRADNER COM- PANY, OF CLEVELAND, OHIO, 'A CORPORATION 0F OHIO.

Giannina APPARATUS.

Application led May 15,

yThis invention relates to an apparatus for grinding or surfaclng blanks. As lllustrating the preferred application of my invention, I have shown it as adapted for grinding or surfacing teeth of gear blanks which teeth have been generated according to the involute rack system. i u l One object of the invention is to provide au apparatus of this character of relatively few parts capable of co-operation to accurately finish or grind gear teeth.

Another object ofthe invention is to provide an improved grinding apparatus of relatively simple construction, whereby assembly and replacement of elements for adapting the apparatus to different sized 'gears or gear blanks may -be readily and easily effected.

Another object ofthe invention is to provide in an apparatus of this character improved means for reciprocating and rolling the gear blank, whereby greater accuracy and uniformity in the finished blank results.

Another object of the invention is to provide an improved mechanism for indexing the gear blank.

Another object of the invention is to provide in an apparatus of this character, means for supporting-the free end of the work spinille to prevent wobbling thereof whereby accurate grinding'of the gear teeth is insured.

Other objects of the invention will be apparent to those skilled in the art to which my invention relates from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a frontv elevation of an apparatus embodying my invention.

Fig. ln is a rear elevation of the apparatus (the. belt being omitted).

Fig. 2 is a fragmentary transverse section on the line 27-2 of Figs. 1 and 4;

Fig. 3 is a fragmentary section on the line 3--3 of Figs. 1 and 4.

Fig. 4 is a fragmentary section on the line l--lf 0f Fig-3. y

Fig. 5 is a section on the line of Fig. 4.

Fig. 5 is an elevation of the parts shown in Fig. 5. l

Fig. 6 is a section on the line 6-6 of Fig. 5. Fig. (i1 is a section on the line tie-6 of Fig,

Fig. 7 is a fragmentary section on the line 3-3 ot' Fig. 1, being similar'to Fig.' 3,.hut showing the 'indexing mechanism in section 1922. Serial No. 561,219.

on the line 7-7 of Fig. 9; certain parts of said mechanism being moved to one position of operation.

Fig. 8 is a section on the line 8-8 of Fig. 7.

Fig 8a is a detail viewof a supporting device.

Fig. 9 is a view of the indexing mechanism, parts being'broken away.

Fig. 9u is a fragmentary view ofthe indexing mechanism, with parts thereof shown in operated position.

Figs. 9* and 9C are perspective views of elements of the indexing mechanism.

Fig. 10 is a fragmentary elevational view of one endv of the apparatus showing the reversing mechanism.

Fig. 11 is a section on the line 11--11 of Figs. 10 and'lQ.

Fig. 12 is a section on the line 12--12 of Fig. 11.

, Fig. 13 is a fragmentary sectional view showing the control l ver.

Fig. 14 is a fragmentary elevational view of the trimmingl mechanism.

Fig. 15 is a section on the line 15-15 of Fig. 14.

Fig. 16 is a section on theline 16-16 ofl Fig. 1.

In the drawings, 1 indicates a main or base frame of suitablel construction supporting near one end an upright frame or column 2, the latter being fixed to the main frame l by any desired means, such as bolts or cap screws 3 (see Fig. 2). The upright frame or column 2 is provided with guides 4 to slidably support a slide 5. 6 indicates a lug or boss, preferably formed integrally withl and projecting centrally from the rear side of the slide 5. The boss 6 is formed with an opening through which extends the lower reduced end of a rod 7. The rod 7 is rigidly held in the opening` through the boss 6 by a nut 8. The upper portion of the rod is screw-threaded, as shown at 10, and such screw-threaded portion engages a nut 11.

Y The nut 11 is adapted to be rotated by suita.- 100 ble means l2. whereby the rod 7 may be raised 'or lowered to vertically adjust the slide 5.

The operating means l2 for the nut 11 may comprise a bevel gear 13 formed integrally with the nut 1l. Iand a beveled pinion 14 mesh- 105 ing with the gearl; The pinion 14 is fixed to a shaft 15, the outer end of which is fashioned to receive a suitable tool, whereby it may be rotated in either direction. The bevel wheel 13 is mounted on a thrust bearing 13 supported on the bottom of a casing 16, which encloses the operating means 12. One side wall of the casing 16 is formed with an opening 17 to form a bearing for the shaft 15. The top wall 16'd1 ot the casing is formed with an o iening. 13 through which the rod 7 extends W en it is moved upwardly. Depending from the top wall 16l is an annular member 16b in which the nut l1 rotates, such member serving as a bearing for the nut 11 and acting through it as a guide :tor the rod 7. 19 indicates a tubular member secured to the top 16 and disposed in alignment with the rod 7 to receive its upper end when the rod is elevated. The casing 16 is preferably provided at its opposite sides with feet 20, which are secured to the column 2 by cap screws 21. The top wall o1' cover 16 is removably held in position by cap screws 22.

23`indicates a head swiveled in any desired manner on the slide 5, whereby the tool, which in the illustrated embodiment of my invention consists o t' a relatively large grinding or abrading wheel A, may be positioned at dit'- ferent angles for well-known reasons. The head 23 may be turned by means of a worm Wheel 24 secured to thehead and engaged by a worm 25 (see Figs. 2 and 4).v The Worm 25 is fixed to a shaft 26 which is supported in bearings carried in lugs 27 provided on the slide 5; the shaft 26 being held against endwise movement by collars 28 engaging the opposite outer ends ot the lugs 27. The shaft 26 is extended at one end and shaped to receive a suitable tool, whereby it may be operated. The head 23 comprises an annular plate 23 adjustably engaging suitable bearings in the slide 5 and a hollow arm 23", which may be formed integrally with the plate 23. 29 indicates a tubular member mounted to move endwise within the arm 23b and adapted to serve as a bearing member for the tool spindle 30. The .surfaces ot the tubular member 29 and spindle 3() are shaped to provide suitable seats for a plurality of anti-triction bearings 31.

32 indicates an element fixed to the shaft or spindle 30 and arranged to rotate it. In the form of rotating meansI herein disclosed, such element consists ot a pulley, fixed to the spindle and'preterabiy arranged between a pair of the anti-friction bearings 31. The tubular member 29 is shaped to provide ample operating space for the pulley 32and its rear Wall as well as the rear wall of the arm 23b is cut away to permit a driving belt 33 to be carried in and around the pulley 32, as shown in Fig. 2. The belt 33 is guided to the pulley 32 by a pair ot' pulleys 34. the belt 33 passing from one pulley 34 around a driven pulley 35, fixed to a main driving shalt 36, and thence around a, guide pulley 3T to the other pulley 34. The pulleys 34, 37, are mounted in suitin the manner to be later set. forth.

able brackets 34a, 37a, respectively, supported by the column 2 in a well-known manner.

The main drive shaft 36 communicates power to other parts or elements of the apparatus I The Shaft 36 may be driven in any desired manner, for example by a pulley, driven by a belt 38 running over ai driven pulley (not shown).

The tool A preferably comprises an annular disk having a planular face a adapted successively to engage the faces of a blank, for example a gea r blank B, as the latter is indexed, in the manner to be later described. The tool A is positioned between a pair of inner and outer plates 39, 40, the inner plate 39 having a hub 41 keyed to the spindle 30 and provided at its outer end with an annular seat 392L for the disldand the outer plate 40 being clamped against the disk by a nut 42 threaded on the hub 41, and acting againstthe plate 40 when it is tightened. 43 indicates a nut screw threaded on the outer end of the spindle 30 and engaging the outer end of the hub 41 to secure the latter on the spindle 30. y 44 indicates a cap plate havingi an annular boss 45 engaging the outer-most anti-friction bearing 3l and through it and seat 46, next adj acent bearing 31 and seat 47, serving to hold the spindle in position axially. v

The bearings 31 on each side of the pulley 32 serve principally to take up the lateral load ofthe pully andare not provided to take axial thrusts, their outer races fitting loosely enough in the tubular member 29 to move axially therein. This vconstruction allows the expansion and lengthening of the spindle 30 due to heat to take place in opposite directions on each-side ot the outermost bearings 31. rlhese latter bearings being very near to the planular tace of the tool A, no appreciable expansion will occur in that direction and hence the `tace ot the tool will not appreciably move out ot its position by expansion ot' the spindle 30.

The cap plate 44 is secured to the outer end of the tubular member 29 by a plurality ot' bolts 48 (Fig. 4). 49 indicates a casing or guard tor the tool A. The casing 49 comprises` a pair of'dish-shaped members 49, 49", having rabbeted vinter-engaging circumferential walls secured together by a plurality ot screws 50, the inner member being provided with a collar 51 fitted on a reduced portion 52 at the outer end of the arm 23" and preferably secured to the latter by suitable screws. The casing members 493.49, are cut away at their lower portions to permit operative engagement of the tool A with the blank B.

53 indicates as an entirety means for moving the spindle 30 endwise to move the tool A into proper grinding position relative to the blank tooth faces. Ot the moving,r means 53, 53a indicates a plate secured to the rear end of the tubular member 29, ypreferably by a plurality of cap screwsI 53", and provided with a rearwardly extending shank 53" having screwthreads 53" with which a nut l54; engages. The nut 54 comprises two sections, 54", 54", the former being recessed to receive the latter section (see Fig. 4). The nut section 54".is provided with a flange 54",'- which is secured by suitable cap screws to the nut section 54". This arrangement permits the nut sections to be adjusted relative to each other to compensate'for wear of the screw threads. The nut 54" is provided with a worm wheel 54d, preferably formed integrally therewith. 55 indicates a worm arranged to mesh with the worm wheel 54", whereby the nut 54 may be rotated; :J'Iheworm wheel 54d engages at its inner side an. annular boss provided on an annular rib 54" provided on the inner wall of the arm 23". The wheel 54" is maintained in operative position against' instrumentalities, I am enabled to regni-aie the boss by a flanged collar 54", the flange of which is secured to the outer edge of the arm 23". The wormy 55 is fixed to a shaftv 55" mounted in a bearing 55", being held on the shaft by a nut`55" (see Fig. 5). The bearing 55" lits into an opening 55" formed in a boss 55" formed integrally with the wall of the arm 23". At its outer end the shaft 55a carries a hand wheel 56, and a disk 56a. The hand Wheel 56 is loose on the shaft 55" whereas the disk 56" is keyed thereto. The circumferential edge of the disk 56 is provided with a' ratchet 56" with which a dog 56", pivoted to the hand wheel 56, engages; the dog 56" being held in engagement with the ratchet 56" by a spring 56d. The hand Wheel56 and disk 56 may be rotated to move the tool spindlev 30 endwise, whereby the tool is moved toward and from theblank B to position it for grinding. By providing a detachable connection between the hand wheel and disk, namely the ratchet 56" and 'dog 56" and correlating with the hand wheel certain or control lthe operation of the tool A. For thispurpose, I provide the following instrumentalities: 57 indicates an annular groove formed in the web portion of the hand wheel 56, this groove being preferably of T-shape. 57", 57" and 57" indicate a plurality of pins having heads adjustably mounted in the groove 57, being clamped against the walls of the groove by nuts 57d engaging screwthrcade'd portions of the pins. The pins 57". 57", serve as stops to ylimit the movement of the hand wheel in either direction, whereas the pin` 57" serves as agage to regulate or determine the adjustment of the tool for carrying out the grinding operation. 58 indicates a stop device'carried by the wall of the arm 23". The stop device preferably comprises a rod 58a having a head member 58". The pin 58tL and head 58" are mounted in a recess or opening formed: in alug 58" carried by the boss 55". The opening in the moved endwise beyond or out of the path of Y movement of the free ends of the stop pins 57", 57", when it is desired to rotate the hand wlieel a greater distance than thatpermitted thereby. To facilitate the operation of thel pin 58a and head 58", the former is provided with a knob 58".

In the operation of the elements just described, the stop 57" is so positioned that it will engage the head 58" in the revolutionl of the hand wheel when the tool A is in engagement with the face of one tooth of the blank B. The stoppin or gage device 57" is SCO` then adjusted around the groove 57 relative to the stop pin 57" a distance corresponding to the Adepth of cut to be made by the tool A `when it is operated.

Assuming that the blank is positioned on the work spindle 64, to be later referred to, the hand wheel 56 is rotated to bring the stop 57 in engagement with thehead 58". The slide or carriage 61, to be later described, is then moved laterally so as to move the blank B away from the tool A. The hand wheel is then adjusted or rotated to bring the stop 57" in alignment with the axis of the head 58". The machine is then set in operation and the grindin 'takes place upon the, faces of the teeth of t e blank B. Should it be desired to grind additional material from the faces of the blank teeth, the hand wheel may be adjusted to move the stop pin 57 beyond the stop 58" and such operations may be repeated until the hand wheel is moved far enough to cause the stop pin 57" to engage with the head 58", which engagement will indicate that the maximum amount of grinding has been effected. To facilitate the positioning of the stop pin 57" relativeto the axis ofthe head 58", the free end of the stop pin 57" is preferably beveled so that it may ride the head 58" and the latter is recessed to form a seatfor the stop pin 57"; this construction permitting the stop pin to ride the end of the head 58b and seat itself inthe recess inthe end thereof and likewise to be moved out of the recess at will. 264 indicates a set screw extending into the recess for the pin 58" and so arranged that upon the movement rearwardly of the pin and its rotation in either direction the collar will en gage the set screw 264 and maintain the pin 58" and head 58" in a retracted position, whereby the hand wheel 56 Will be free to rotate. The free end of the shank 53" is preferably reduced to form a shoulder against which a stop device, such as a washer 59, is clamped by a nut 59, the stop device 59 being arranged to engage the nut 51 and limit the movement. of the spindle 30 and tubular member 29 endwise in a direction away from the blank B. 591 indicates a casing'iitted to the outer edge of and supported by the collar 5i". The casing 55)" encloses the outer end of the shank 53" and prevents dirt and other material from getting into the arm 231. As shown in Fig. 5, the wall of the arm 23" is shaped toyt'orm a housing 59 for the nut 51 and worms 54, 55.

60, 60, indicate a pair of ways or guidegrooves provided on the -trame 1 and adapted to receive shoes or guides 60, 60a, on the lower side of the carriage. 61, whereby the latter may be reciprocated for reasons which will later appear. The arriage 61 is provided with a pair of spaced pillow blocks 61a, 61a, to whiclrare secured cap members 62, 62, respectively, forming bearings 63, 63, for the work piece or blank carrying spindle 64. The spindle 64 is preferably formed in sections, as follows: a main section 61 and a detachable section 6l". The main section 64 atone end extends through and rotatably iits a sleeve 65, which in turn is rotatably mounted in the bearing 63;y at its opposite end the shaft section 64 is enlarged, as shown at 64"', such enlarged portion rotatably fitting the bearing 63a. The enlarged portion 64 of the shaft is formed with a recess 64d of tapering shape extending inwardly from its outer end, and such recess 64 receives the inner tapered end 64e of the spindle section 64. The spindle sections 611;a and Gill are preferably secured together by the following instrumentalities: 66 indicates an opening extending through the main spindle Section 61. 66a indicates a bolt extending through the opening 66, the head ofthe bolt engaging the outer end of the spindle section 64 and the inner end of the holt being screw-threaded into an opening 66b formed in the inner end of the spindle section 64". By tightening the bolt 66, the tapered spindle end 64 will be drawn into the opening 6l and thus rigidly secure the spindle section 64 to the section 61a. The outer end of the spindle section 61 is preferably reduced to form a Shoulder 67, against which the blank B may be clamped in any desired manner, for example, by a lint 67. The end of the shaft section 64b, beyond the threaded portion for the nut 67a is reduced as shown at 67b and its end is formed with an opening or recess 67 arranged axially' of'the shaft 64". By means of the construction just described, it Will be seen that that portion of the work carrying spindle to which the blank B is clamped may be detached or removed from the main spindle section and another spindle section provided, whereby differentsized blanks may be readily `positioned for grinding or finishing b v the tool A.

68 indicates means for supporting the outer or free end of the work carrying spindle seclffoiase tion 61, whereby it may be maintained against wobbling to insure relatively accurate grinding or iinishing of the sides of the gear teeth. (if `the supporting means 68, 69 indicates an arm formed integrally with the car'- 'riage 61 and provided with guide-ways 70 in which a slide 71 is adjustably mounted. The slide 71,is provided with al bracket 72, which carries at its free end a seat 7 3. The seat 7 8 is shaped to receive a supporting member 73a, preferably formed with an opening 731 in which a center 7 3 is mounted, these elements being arranged to support the center in axial alignment with the shaft section 64b with the center projecting into the recess 67 c in the outer end of the shaftsection. The supporting` member 73a is secured in the seat 7 3 by a cap screw 7 3d. The inner end of the supporting member has a projecting collar'73e provided with stepped surfaces, the outer one of which serves as a guide for a cup member 74. and the inner one of which serves as a support. for a coiled spring 74a which tends to push the cup member 74 outwardly against the end of the shaft section 64b so as to en-` close the center and prevent water and grit from getting into the recess 67 c or around the center, the cup member being formed with an opening through which the center 73c extends. The arm 69 is provided with a longitudinally extending rack 75, with which engages a. rack pinion which is carried at the inner end of a shaft 7 5, exten-ding through and mounted in an opening formed in the slide 71. At its outer end, the shaft 7 5a carries a wheel 76, whereby the shaft may be rotated, such operation serving to move or adjust the slide 71 in the guideways and thereby move the center 73c axially of the spindle 64 so that it may be moved into and out of engagement with the spindle section 64b. The slide 71 may be fixed in any adjusted position by suitable means, such means in the illustrated embodiment of the invention comprising a wedge bar 7 7 extending through a recess 78 formed in the slide 71 and so disposed that one side of the wedge bar 77 is arranged to engage one of the Ways 70 of the arm 69. The wedge bar 77 isformed with one or more openings having threaded walls to receive the threaded ends of rods 7 9 rotatably mounted in suitable openings formed in the wall of thel slide 71. At ytheir upper ends, the rods 79 are formed with handles 79 by means of i which they may be rotated, such operation serving to move the wedge into clamping engagement with the adjacent way 70, and the slide against the other way 70. y

In the herein disclosed illustrated embodiment of my invention, the gear blank is given a rolling movement such as is required in carrying out the generating principle, on

which the blank was cut. For this purpose I preferably employ tapes which are arranged to wind and tmwind about a segment cona driven shaft which operates to oscillate the work spindle 64, whereby the gear blank 'B is given the rolling motion in the manner just referred'to. The shaft 80 is driven first in one direction and then in the opposite direction Iby a suitable reversing mechanism indicated as an entirety at 81 (which mechanism is shown in detail in Figs. 10, 11 and 12), to which reference will later be made. The outer end lof the shaft 80 has bearing in a. pair of spaced lugs 83, 83', which are preferably formed integrally with a. casing member 84 supported by the adjacentpillow block l61a andcap member 62 (see Figs. 3 and 7 The casing member 84 co-operates withfa. casing member 84a to" enclose an indexing mechanism indicated asan entiret at 85. The free end of the shaft l80 isprovi ed with a washer 86 and nut 87, which bear against a thrust bearing 88 supported at the outer end of the lug'83, thisbearing takingthrusts of the shaft 80 whenit is rotating in one direction. 89 indicates a worm fixed to the shaftv80 and disposed between the Ilugs 83, 83. The inner side of the lug 83 is provided with a thrust bearing 90 which takes thrusts when the shaft 80 is rotating in the opposite direction. 91 indicates a worm wheel segment connected by suitable bolts 92 to a disk 93 which is secured by cap screws 94 to the sleeve 65 .and forms one element of the indexing mecha` nism 85, the latter thereby serving as a connection between the sleeve 65 Aand the work spindle 64, whereby the spindle may be oscillated by the shaft 80. 95 indicatesa segmentsurrounding the spindle 64 or a portion thereof andserving as 'the wall or surface aboutwhich tapes 96, 96, wind andv unwind. As will be understood, the segment 95 has substantially the same pitch 'diameterasthat of the blank B to be ground and is removably secured to the spindle 64 to permit the substitution of segments having pitch diameters substantially corresponding to any s ize blank which may be mounted on the spindle. As shown ir Fig. 8,the lower portion of the segment 95 is cut away `whereby it maybe placed on and removed from the spindle 64. At its opposite ends the segment is provided with ianges 97, '97; the flange 97 being adapted to be clampedto a fiattened lug or shoulder 98 projecting from theinner end of the'sleeve 65, and the fiange 97a being adaptedto be clamped against a flattened wall on one'side of a supporting device 99, which loosely tits the spindle 64; this arrangement permitting (1) the segment 95 to have a fixed relation with the spindle 64 when the spindle is' being oscillated as will be laterset forth and (2) the spindle 64 to be rotated relative to the sleeve 65 and segment 95 to effect indexing lof the gear blank B. 97 97 n" indicate cross members extending transversely of the spindle 64 and engaging the fianges 97, 97, respectively. 100 indicates boltswhich extend through openings formed in the opposite ends of the cross members 97 97a', and engage cross members 101, 101, provided atthe opposite ends of a clamping plate 102, the cross member 101 engaging a lug or shoulder 98L projecting from the vsleeve 465 but at -the opposite side of its axis from the lug 98, and the cross-.member 101 engaging a flattened wall at the other sidefof the supporting device 99, whereby the bolts may operate through the cross members to 'clamp and removably support the segment 95 in position. The supporting device 99 (see Fig. 8a) comprises an anvnular shaped member having at opposite sides around rods 103 and clamped against the. v

plate 102 by a bar 104,'cap screws 104 being provided vto secure the bar 104 against the ends of the tapes. 105 indicates a shoe member disposed substantially tangentially to the segment 95 and extending to eitherside of the spindle 64 and ina plane parallel to the plane in which the spindle moves. 106, 106, indicate a plurality of connecting devicesca-rried by the shoemember 105, (preferably disposed at the opposite ends-thereof) for connecting the outer ends of the tapes thereto. In the preferred form of construction I use four tapes, two of which wind around the segment 95 in one direction and are connected to the connecting devices 106 and the remaining two i of which wind around the segment 95 in the opposite direction and are connected to the e connecting devices 106f; furthermore, the tapes of each pairlalternate with the tapes of "the other pair. Each connecting device 106, `or 106, comprises a lever 106 pivoted upon a -rod or bolt 107 mountedin a. standard 108,

a pin 109 aboutwhich the end of each tape is folded and a clamping plate 110 engaging the folded tape end and clamped thereagainst' by a bolt 111 screw-threaded into an opening inthe l-lever 106". By pivoting each lever 106b on the shoe member 105, its outer end may be adjusted to put the tapes connected to it under the proper tension. yThe adjustment means for each connecting device 106, 106,

` member 1.05 may be raised or lowered relative t .to the'splndle 64 so as to position it'tangen- .tially to any size of segment 95 which may be comprises a screw 111, fitting and extending through an opening 111b formed in the wall of the connecting device and. engaging at its free end the adjacent end wall of the shoe member 105. By screwing thev screw 111 inwardly, it will cause the device 106 or 106'1 to swing outwardly and thus put the tape connected to the latter under the desired tension and adjust its effective'length. The upper end of the shoe member 105 is shaped to provide a pair of bars 112 having flanges 113 slidably fitting a pair of guides 114 provided on the lower end of a vertically adjustable support 115. The shoe member is iixedly connected to the support 115 by a lurality of cap screws 116 extending throuo openings 117 formed in the flanges 115a oia the support 115 and fitting screw-threaded openings in the bars 112.- To permit of adjustment of the shoe member l105 relative to the support 115, the openings 117 are elongated (see Fig. 8) so that upon loosening the cap screws 116, the shoe member may be moved to the desired position and then fixed by tightening the screws 116'. It will be noted that the bars 112 and the guides 114 extend in a. direction at right angles to the axis of the spindle 64; as the connecting devices 106, 106aare carried by the shoe memlber 105, it will be seen that the adjustment of the latter along the guides' 114 will simultaneously move the connecting devices relative to the spindle 64.

117 indicates a means for adjusting the shoe member 105 relative to the support 115. Of these means, 118 indicates a boss depending froml the support 115, preferably between the bars 112. 119 indicates a screw threaded opening formed in the boss 118, and extending parallel to the bars 112. 120 indicates an opening formed in one end wall of the shoe member 105 in alignment with the openin 119. 121 indicates a rod extending throng the openings 119, 120, its inner screw threaded and engaging t e threads of they opening 119. The rod 121 is provided with collars 122, 122", engaging the opposite faces of the end wall in which the opening 120 is formed and serving to prevent endwise movement of the rod 121 relative to the shoe member 105 when the. rod- 121` is rotated, so that its rotation in the opening 119 will effect a movement of the shoe member 105 relative to the support 115. The outer end of the rod is preferably shaped to receive a suitable i500 123 indicates a pair of guides provided on the column 2 and engaging guide walls 124 provided on the support 115, whereby the latter is adjustably connected to and supported by the column 2. The guides 123 and guide walls 124 extend vertically so that the shoe used in the apparatus. At its upper end the portion being support 115 is formed with a screw-threaded opening 125, in which a screw threaded rod 126 .is adapted to rotate. The rod 126 is supported at its upper end in a bearing 127, being hel-d against endwise movement therein by collars'128, 129. The rod 126 is provided at its upper free end with a crank 130 by means of which it may be turned.y The bearing 127 is provided at the outer end of a bracket 128 supported by the adjacent side wall of the column 2.

Of the reversing mechanism 81, I provide a set of change gears, referably comprising a pinion 131 fixed to t e driven shaft 36(see Fig. 12) and a gear 132 meshing with the pinion 131. The gear 132 is fixed to and continuously drives a counter shaft 133. The shaft 133 is mounted in suitable bearings 134, 135, provided in a. housing 136 which is bolted to the mainframe as shown in Fi 1%. The housing 136 ma be provided wit an opening 137, adapte to be closed by a cover 138.

139, 140, indicate a pair of geais lixed to the countershaft 133; t e former-n'ieshing. with and transmitting power through an idler 141 loosely mounted'on a shaft 142 (see Fig. 11) to a gear143 loosely mounted. on a, supplemental shaft 144; and the latter meshing with a gear 145. loosely mounted on the shaft 144.

The shaft 144 is preferably mountedin suit-- able anti-'friction bearings 146, 146, the former being supported in a suitable seat formed in a collar 147, and the latter being removably mounted a seat formedl in the outer end walls of the housing136 (see Fig. 12) and held in posit-ion by a detachable `cap 148. The ears 143, 145, are respectively provided on t eir opposing sides with collars' 149, the free ends of .which are shaped to provide clutch elements 150 with eitherjof which a clutch member 151, splined to the shaft 144 is arranged to be engaged. The clutchmember 151 is provided with an annular groove" 152 in which a yoke or other suitable device 152u fits, whereby the clutch member 151 may be moved endwise ofV the shaft 144 into engagement with one of the clutch l'elements 150 and out of engagement with the other clutch element and yinto vengagment etc., it beino' understood that .(1) when the vclutch mem er 151 engages the clutch element 150 for the gear 145, the shaft 144 will be driven in one direction 4and (2) when the lclutch member 151 engages the clutch element 150 for the gear 143 the'shaft'144 will be drivenin the o posite direction-such reversed direction eing effected by interposing the idler 141 beween the gears 139and 143. The yoke member 152a is provided 'with studs152b (one being shown in Fig. 10) which'l are engaged by a-lever`152, mounted on a stud shaft 152. 153 indicates a gear fixed to the shaft 144 and meshin wit a gear 153 loosely mounted on the s aft 80", the outer end of which is lmounted in suitable-bearings provided in the housing 136. For reasons which will later appear, the gears 153, 1531 are preferably spiral gears, and the gear 153 is relatively wide so that it may move longitudinally of the sh aft 144 without being disconnected from the gear 153% 154 indicates a clutch interposed between the gear 153a and the shaft 80" and controlled manually by a handle or lever 155. rl`he clutch 154 comprises a clutch element 154a fixed to the gear 153a and a sleeve 154b splined to the shaft 801 and having a clutch element 154C engageable with the clutch element .154% The sleeve 154" is operated endwise of the shaft 80b by a yoke member 155', slidably mounted on a rod 156, and the lyoke member 155` is operated by a lever 157 fixed to a rock shaft 158 mounted in a cover 159 (see Fig. 13) bolted in any suitable manner, as indicated at 160, to the housing 136. The rock shaft 158 is operated by the handle or lever 155. 161 indicates a worm preferably integrally formed with a sleeve 161a fitting on and fixed in any desired manner to the shaft 80". The worm 161 meshes with a worm wheel 162 fixed to a transverse shaft 163 mounted in suitable bearings 164, as shown in Fig. .11.. At `its outer end, the shaft 163 carries a disk.165 on which are mounted a pair of spaced stops 166, 167. 168 indicates a lever pivoted at 169 to a boss 170. One end of the lever 168 extends upwardly between the stops 166, 167,

1 so as to be engaged thereby. The opposite worm wheel 162, will rotate the transverse' end of the lever 168 is pivotally connected to a link 171 which in turn is pivotally connected to the lever 152c at 263. The shaft 80 is ypreferably formed in sections, one being indicated at 80, and the other indicated at 80h. The section 801 comprises a sleeve portion 80c into which the adjacent end of the section 80a fits. The remaining portion of the shaft section 80b is reduced to receive the worm sleeve 161, gear 153 and clutch sleeve 154", such arrangement permitting the provision of thrust bearings 172 between the shaft 80y and tibi; walls of the bearings therefor (see Fig.

The operation of the reversing mechanism may be briefly described as follows: The power of the shaft 36 is transmitted through the change gears 131 and 132, shaft 133 and one of the gears143, 145, to the shaft 144, accordingly as the clutch member -151 is engaged with the one or the other thereof. The shaft 144 through the gears 153, 1532 and clutch 154 will rotate the shaft 80 and' the latter in turn, through the worm 161 and shaft 163. The latter shaft rotates the disk 165 and causes one of the stops, for example stop 166, to engage the lever 168 and move it about its pivot,"such operation serving to disengage the clutch member 151 from one gear clutch element 150 and engage it with the clutch element 150 of the `other gear. The

shafts 144, 80` and 163 will then rotate inthe opposite direction until the stop 167 engages 154 is thrown out by movement of the llever 17 2 indicates as an entirety means for operl f ating the lever 168 with a relatively quick movement to throw the clutch member 151 into engagement with either of the clutch elements following its d1seugagen'1ent fromeither one thereof. Of. these means, 173 indicatesa lug carried by the lever 168. 174 indicates an arm pivoted at 175 and carrying a pair of cams 176shaped to form a shoulder over which the lug rides from one cam 176 to the other. 177 indicates a spring connected to the arm 174 and to an eyebolt 178 and tending to swing the arm 177 upwardly about its pivot. Vhen the clutch member is in one position, that is, in engagement with one of the clutch elements 151, the lug 17 3 is disposed in engagement with one of the cams. Vhen one of the stops engages the lever 168 and moves it toward its other position, the lug cams, the spring ,acting through the other l cam 176 and the lug 173 will cause the lever 168 to swing with a relatively quick movement over to its other position. When the reversin g mechanism operates to reverse the ro tation of the shaft 80, these elements operate in the. Fame manner in the opposite direction. By forming the link 171 with an elongated slot to receive the pivot provided'between it and the lever 168, the latter, when operated in either direction by the action of the adjacent cam, will attain considerable momentum hefore the pivot engages the end wall of theslot in the link 171. so that the latter will be quickly and positively operated. The lug 173 is preferably provided with a roller 173 whereby it may ride the cams with minimum friction.

It will be noted from the: foregoing description that the shaft 80 is rotated for a predetermined number of revolutions in either direction. By adjusting either stop 166, 167, the shaft 8O may be rotated in either direction a larger or smaller' number of times. For this purpose, each of the stops 166, 167, comprises .a pin 179, having a head slidably fitting an annular T-groove 18() formed in the disk 165, the` pinl having a threaded portion to receive a nut 181, whereby the head may be clamped againstthe walls of the groove 180. e

182 indicates a pair of collars fired to the shaft 144 and disposed upon opposite sides of the gear 153. 183 indicates a spring coiled around the shaft 144 ateither side of the gear 153 and disposed between it and the adjacent collar 182. As clearly shown in Fig. 12, the ear 153 is splined to the shaft 144 b ut is ree to move longitudinally thereof in either direction against the tension of one of the springs 183. As already described, the gears 153, 153, are spiral gears so that their resulting meshing action causesv a thrust in lone direction or the other accordingly as shaft 144 is transmittin power. Accordingly, when the rotation ofy the shaft 80 is reversed and it, throughthe tapes 96, 96, startsto move the carriage 61 in the corresponding opposite direction, the reaction of the spiral teeth of the gears 153,153, incident to picking up the carriage intransmitting power through the spiral teeth of the gears 153, 1538, will cause the gear 153 to slide endwise of the shaft 144 against one of the springs 183 which will thereupon absorb or cushion such thrust movement; the effect of which will be to start the movement of the carriage in the reversed direction relatively slowly without jerking it. The springs 183 are preferably of a size to return the gear 153 to substantially its mid-position after the carriage 61 has been reversed and started on its return movement.

Of the indexing mechanism 85, 18.L indicates a block secured in any desired manner, for example, by dowel pins 185 and a cap screw 186 to the disk 93. The block 184 is provided with a pair of gilide walls 184, preferably extending parallel to a line that is radial of the axis of the work spindle 64 and arranged to slidably 'support a plunger 187. The face of theplunger 187 engaged by a pair of plates 187, whereby it is held in the guides 184?. 188 indicates a dog carried at the lower or inner-end ofthe plunger 187 and arranged successively to pro3ectr into slots or recesses 189 formed in the circumferential edge of a plate 190 fixed, preferably through a hub member 260, to the outer end of the work spindle 64, by a nut 261. The slots or recesses 189 are uniformly spaced around the plate 190 and correspond in number to the number' of teeth ofthe blank B to be ground. W'hen the dog 188 is in one of the slots 189 the disk 93 and plate 190 are connected together so that the power of the shaft-80 is transmitted therethrough to rotate` the spindle 64 and to translate such rotary movement into rectilinear movement of the slide or carriage 61", whereby the generating movement of the gear blank B may be effected during engagement of the tool A therewith, as already described. Such engagcnient takes place during the movement of the disk-93, plunger 187, plate 190 and spindle 64 in an anticlockwise direction (as viewed in Fig. 9) to their extreme position and back to their starting position. As these elements near the end of their movement in the clockwise direction, the blank B moves out of engagement with the tool A and indexing of the blank takes place, that is, the dog 188 disengages the adjacent slot 189, and the plate '190 is locked against rotation so that the dog can move around the lplate 190 and engage the next or succeeding slot 189 to connect itself with the plate to move it in' the anticlockwise and then back again, such operations being repeated until all of the teeth ofthe gear blank B have been ground. 191 indicates a rollermounted on a shaft 192 extending through openings formed in the Wall of the dog 188 and the plunger 187 and held in position by a nut 193, said shaft co-operating with a screw 194 to rigidly secure the dog to the plunger. 195 indicates a rack provided at or'falong one side of the plunger 187 and arranged to be engaged by a segment of a rack pinion 196 (see Fig. 9). The segment 196 1s carried by a collar 196a rotatably mounted on a stud shaft 197 mounted on the disk 93. The collar 196 is provided with a tail-piece 197 which engages a trip 198 pivotally mounted in a. block 199 fitting in an opening formed `in the casing member 84. The trip 198 is maintained against a stop 200 by a spring 201. In the movement of the disk 93 and other elements above referred to in the clockwise. direction, as viewed in Fig. 9, the tail-piece is engaged by the trip 198, such engagement causing the rotation of the collar 196n as the tail-piece rides the trip; the collar in turn moves the rack pinion segment 196 and it operates the plunger 187 and disengages the dog' 188 from the adjacent slot 189 in the plate 190. 202 indicates an arc shaped guide arranged to receive the roller19l as the elements move clockwise. The guide 202 is positioned to receive the ,roller 191 prior to the radial movement of the plunger by the collar 196, 'The guide 202 is secured to a support 203 the opposite ends of which are slidably .mounted in a pair of guides 204, 204, disposed in a radial line and carried by integral walls of the casing member 84. As the roller 191 enters the guide 202 prior to the outward movement of the .plunger 187, it will be seen that when the latter `is operated, the roller 191 .will operate through the guide 202 to move the support 203' radially out\vardly. against the tension of one or more springs 204, connected theretoiland to fixed devices 205 provided on the casing ember 84 (see Fig. 9). 206 indicates a paWl pinted an .a shaft 206 carried by a bearing block 207. The block 207 l is mounted in an elongated opening formed in the support 203, being maintained in position against movement endwise of the slot by The pawl 206 ispositioned to project into one of the slots 189 after the dog has been removed therefrom.

The function of the pawl is to engage the plate 190 and lock it against movement following the disengagement of the dog 188 therefrom. The pawl is preferably arranged l to enterthe slotl 189 from which the dog 188 hasmoved, the plate 190 being flanged as shown at 190'* so lthat the lwalls of the slots 189 will -be in the path of movement of the pawl 206. The pawl 206 is provided with a tail 209 to which one of the springs 204 is connected, thus permitting the pawl 206 to yieldinglyengage the inner wall of the flange 190, when the support '203 .is moved -outwardly, ready to enter a slot 189; asit moves clockwise.

As already dog from the plate 190, as these parts move clockwise. As soon as the. `tail-piece 197 passes the trip 198, 'the plunger 187 and the dog 188 are free to move inwardly radially, being acted upon by the springs 204 acting through the support203 and guide 202. However, these elements are maintained approximately in .their outward position 4by the circumferential edge ofthe plate 190 with which the dog 188 engages after the tailpiece 197al passes the trip 198. As the disk 93Y and'fplunger 187 continue to move clockv wise, the dog 188 will ride on the'circumferential edge of they plate 190 until it reaches the next slot 189 into which it will project andpermit the springs ,204 to vmove the s'upport 203 and elements carriedgby it inwardly to their locking position, thus causing the pawl 206 to `disengage the adjacent slot 189. kThis operation again secures the disk 93 and late 190 together, thereby completing the indexing of the blank B. The direction of rotation of the shaft is reversed follow.` ing the latter operation, so` that theV nextv grinding operation can be effected.

The trip 198 is pivoted so that it may swing in one direction and permit the tailpiece 197 toJ pass it when the elements are moving counter-clockwise, To prevent disengagement of the vdog 18,8 fronieach of the slots 189 throughoutthat portion of the movement of the elements during the grinding operation I provide the following instru mentalitiesl'.'

209vindicates an arcshapcd member carried by the casing member 84 and extending throughout thejpat-h I of movement of the plunger during that portion of, its movement in which the'grindingoperations take place. i The platey 209 is secured to the'casi-ng mem' ber 84a by a pluralityfof Vcap screws 210. 211 indicates alever pivotally mounted upon the stud shaft 197 and carrying at'itsy outer end a pin 212 on which aroller 213 is .loosely mounted, the latter serving to roll on the plate set forth, the trip 198 lactuates` the collar 196* which in turn disengages thel 209. The collar 196? is provided withanarm 214 which is disposed between a pair of abutments 215 provided on the tail-piece 216 of the lever 211. The arm 214 is vyieldingly maintained against one of the abutments by a flat spring .214K lAs will be understood from Fig. 9, the wall 209,wi1l prevent'movement vof `the lever 211 about the shaft 197 and the lever 211, through the engagement of its tail-piece 216 with the arn 214, will prevent lrotation of the collar 196 in -a counter-clockwise direction (as viewed in Fig. 9), so that the plunger 187 will be locked against movement upwardly in a radial direction. Asa result of this construction, the dog.188 will be maintained in the adjacent slot 189 during the grinding operations. 'As shown in Fig. v9, the are shaped wall 209 terminates at a point ahead of the position occupied by the plunger 187 when it is moved upwardly by v:reason of the engagement of the tail-piece 197n with the trip 198, thus permitting movement of the plunger following the disengagement of the blank B from the tool A.

The casing members 84, 84, are preferably connected together by devices, indicated as an entirety at 216", whereby the y the trip 198 maybe adjusted to e ect operation of the plunger 187 at any desired point throughout the travel of the disk 93.v For this osition of l purpose the ,flanges of the casing members j 84, 84a, are formed with openings 216", to receive .clamping elements, such as suitable screws 216, the openings 216,b in the casing ,member 84 beingy elongated as shownv in Fig.A `-9, sothat it may be moved about the axis clamped to .the

of the spindle 64 and then casing member 84.

217 indicates as an entiretymeans for preventing thegrotation of the tubular member l29 and for locking it in any of the positions to which it may be moved by the hand wheel 56. Of these means 218, 218, indicate a pair 'i i which issecured to thickened walls of the arm `23b by a plurality of capjscrews 222. 223 indicates a plunger slidably ittin an 219 indicatesy a pin extendingopening 224 formed in the arm 23"- ina'. ign-l ment with the opening 220 and engaging one l wall ofthe groove 218. Theplunger is con-l,

nected at itsY outerfend to a rod .225 which has screw-threaded engagement with a plat-e 226 screws 227 to thickened wallsv securedby cap of the arm 23 move it endwise inwardl Rotation of the rod 225 will 0r outwardlyaqcording to the direction o its rotation when mechanism for trimming the planular face a of the tool A. Of the trimming mechanism, 228a indicates a diamond projecting from the outer end of a sleeve 229, the diamond being supported in the sleeve in a well-known manner and positioned against the inner end of a plunger 230 which has screw-threaded connection with the inner wall of the sleeve 229 whereby it may be moved endwise. The sleeve 229 is mounted in an opening 231 formed in an arm 232 which is formed integrally with and extends laterally from a' shaft 233. The shaft 233 is rotatably mounted in a bearing 234 provided on a standard 234 secured by a plurality of bolts 235 to the wall of thc arm 23h. The sleeve 229 is secured in the opening 231 by a suitable cotter pin 235. The shaft 233 has a. reduced portion 236 and surrounding such reduced portion is a sleeve 237 provided at one end with a worm wheel 238 with which a worm 239 meshes. The worm 239 is connected to ashaft 240 mounted in an opening formed in the standard 234. The shaft 240 is provided with a crank 241', whereby it may be operated to rotate the shaft 233 and swing the arm 232 from an inoperative position beyond the periphery of the tool A to an operative position, in engagement with the planular face of the tool A, the'casing member 49b being formed with an opening 242 to permit the positioning of the diamond 228"L as shown. The diamond itself may first be positioned relatively to the casing by adjusting the'sleeve 229 axially in the arm 232 until, as shown in Fig. 1, `the diamond touches one wall of the opening 242 in the casing member 49". Thenv when the arm 232 has been swungto bring the diamond in front of the tool face,the tool A maybe adjusted axially in the manner described hereinbefore to locate `it relatively tothe diamond (and therefore relatively to the wall of the casing) g or to enable/the diamond to cut and dress the tool A wall of the casing. Since the position of the casing is fixed relatively to the Work carrying spindle 64 and gear B, by thus positioning the diamond relatively to the casing and then locating the face ofthe tool relatively to the diamond the face of the tool can .at any time be accurately located relatively to the work piece or gear B.

The wall ofthe casing is used as vthe reference point or reference station relatively to which the diamond is adjusted, because of its convenient` location? But Obviously any suitable point or station that is xed relatively to the frame of the machine or to the gear may be used.

The outer end of the shaft 233 is prefer-` ably provided with screw threadsto take a' nut which engages a coiled spring 243 engaging the sleeve 237 and through it serving to yieldingly maintain the shaft 233 in the bear- 7 ing 234- with the shoulder 244 at its inner end in engagement with the adjacent end of the bearing. y

245 indicates a hand wheel having a hub 246 loosely fitting the outer end ofthe shaft (see SU Fig. l2), being held thereon by any suitable means, for example, by a washer 247 and a nut 248. The inner end of the wheel hub 246 rotatably `fits the outer end of a bushing 249 which forms one bearing for the shaft 80. The end wall of the hub 246 is provided with Clutch elements 250 adapted to be engaged by the clutch elements 251 on the adjacent end of t-he clutch member 154, so that when the latter is disengaged from the gear 153, it will 90v connect the shaft 80 to the hand wheel 245. This Aconstruct-ion permits the shaft 80 to be manually rotated to adjust the carriage or slide 61 or the gear blankfB relative to the tool A.

252 indicatesa shaft extending from the front side of the frame 1v to the rear side thereof. At its rear end the shaft 252 is provided with a rack pinion 253 which engages a rack 254. The rack 254 is connected to a belt shifter 255 and operates the be1t38 from the loose pulley 256 to the fast pulley 257 in a wellknown manner. At its front end the shaft 252 is provided witha crank 258, whereby it may be readily` operated.

It will be understood that many alterations and' widely differing embodiments of the invention will suggest themselves ',to those skilled in the art' to which my invention relates Without departing from the spirit and Il" scope thereof. 'The disclosures and description herein are purely illustrative and are not intended to be in any sense limiting.

lVhat I claim is:

l. In apparatus of the class described, the U5 combination with a tool and a carriage on which a blank is mounted for engagement bv the tool` of means for reciprocating saidcarriage, said means including a driven shaft. a to a true surface 1n proper relation to the.

countershaft having connections with said driven shaft, a supplemental shaft, alternative connections between said counter and supplemental shafts having a clutch member arranged to engage either of said connections. whereby said-supplementalshaft mav be. driv- V25 en in either direction, a separate shaft having operative connection withsaid carriage, means operated` by said separate shaft for shifting said clutch member` and means hetween said supplementaland separate shafts 130 supplemental shaftalternately in opposite4 directions, a shaft having operative connection with said carriage, means operated by said last n'ientioncd shaft for shifting the elements of said driving means which controls the direction of rotation of said supplemental shaft, and means between said supplemental shaft and the last mentioned shaft for driving the latter and cushioning the carriage in effectingreversal of movement thereof.

3. In apparatus of the class described, the combination with a tool and a carriage on wliicha blank is mounted for engagen'ient by the tool, a supplemental shaft, means for driving said shaft alternately in opposite directions, a shaft having operative connection with said carriage, means operated bysaidlast mentioned shaft for shifting` the element of said driving means which controls thedirection of rotation of said supplemental shaft, a gear train between said supplemental shaft and the last mentioned shaft for driving the 1atter,two of the gears of said gear train being helical gears and one movable relative to the other on its axis, and springs engaging said movable helical gear and arranged to take tue thrust thereon incident to the inertia of the carriage ineifecting the reversal of movement thereof.

4. 'In apparatus of the class described, the combination with a tool and a carriage on .which a blank is mountedfor engagement by the tool, a supplemental shaft, means for driving said shaft alternately in opposite direct-ions a shaft having operative connection with said carriage. means operated bv said last mentioned shaft for shifting the element of said driving means which controls the direction of rotation of said supplemental shaft, helical gears on said shafts 'for transmitting the power of the supplemental shaft to the othershaft, one of the said gea-rs being slidable. on its shaft. and springs engaging said slidable gear arranged to take the end thrusts thereof incident to the inertia of the carriage in effecting the reversal offmoveuicnt thereof.

5. In'apparatus ot' the class described, the

'combination with a tool and a carriage onv which a blank is mounted for engagement by the tool. of ,means for reciprocating said carriage, said means including a driven` shaft, a countershaft having change gear connections with said driven shaft, a supplemental shaft, alternative connections between said counter and supplemental shafts having a clutch member arranged to engage either of said connections, whereby said supplemental shaft may be driven in either direction, a separate shaft having operative connection with said carriage, means operated by said separate shaft for shifting said clutch member, and means between said supplemental and separate shafts for driving the latterl and cushioning the carriage in the reversal -o't' movement thereof?,

6. In apparatus" of the class described, the combination with a carriage adapted to be reversed of reversing means therefor including a supplemental shaft, means for driving said shaft alternately in opposite directions, means operatively connecting the supplemental shaft and the carrave to reciprocatively move the carriage,`tlhe said means including two power transmitting element-s one having an inclined surface upon which it is engaged by the other, the two elements being thereby adapted to move relatively when transmitting energy, and aresilient element opposing said relative movement and arranged to accumulate a part of the energy delivered by the supplemental shaft to stop and reverse the carriage.

7 In apparatus of the class described, the combination with a movable carriage of means for reversing its direction of motion, including a movable clement adapted to transmit reciprocatory movement to the carriage alternately in opposite directions through two power .transmitting elements one having an inclined surface upon which it vis engagedby the other, the two elements-being thereby adapted to move relatively when transmitting energy, and a resilient element opposing said relative movement and arranged to accumulate a part of the energy delivered by the movable element to stop an reverse the carriage. n i

8. In a machine, a cushioned power transmittingI device including `a rotating power supplying element` al rotating power receiving element, a train of gears connectingl the two elements two of which are helical gears and thereby adapted to move relatively. axially, when transmitting power, and a resilientelement opposing said relative movement and arranged to accumulate a part of the energy delivered by the power supplying element when above -a pre-determined amount. t

5). In apparat-us of the class described, the combination of a frame, a carriage mounted to reciprocate thereon. a pair of supports on said carriage. a work-carrying spindle rotatably mounted in said supports, a sleeve interposed between ysaid spindle and one of said supports. a segment disposed between said supports invparallel relationship to the axis of said spindle and engaging said sleeve at one llt) end, means for supportingthe other end of 10. In apparatus ofthe class described, the

` combination of a frame, a carriage mounted to reciprocate thereon, a pair of supports on said carriage, a work-carrying spindle rotatably mount-ed 1n said supports, a sleeve 1ny terposed between 'said spindle and one of said supports, a segment disposed between said supports, means for connecting one end of said segment to said sleeve, and a device rotatably fitting said spindle to which the other end of said segment is connected.

11. In apparatus of the class described,

- the combination of a frame, a carriage mounted to reciprocate thereon, a pair of supports on said carriage, a work-carrying spindle r0- tatably mountedin said supports, a sleeve interposed between said spindle and one of said supports, a segment disposed between said supports, means for connecting one end of said segment to said sleeve, and a device rotatably fitting said 4spindle to which theother ,end-of said segmentis connected, and means 'for connectingsald sleeve and spindle together, and means operating` through said connections for oscillating said spindle.

12. In apparatus of the class described, the combination of a frame, a carriage mounted to reciprocate thereon, a tool carried by said frame, a work-carrying spindle on said carriage, means for oscillating said spindle and reciprocating said fcarriage, means carried by said carriage and engaging said spindle beyond the blank carried thereby for steadying the outer end of said spindle.

'13. In apparatus of the class described, the combination of a frame, a carriage mounted to reciprocate thereon, a tool carried by said ried thereby, a support adj ustably carried-f by f the said carriage for supporting said center, and means enclosing said center and-engaging the free end of the spindle for preventing foreign substances from contacting with said center and shaft end.

15. In apparatus of the class describedthe combination'of a frame, a tool on theframe,

acarriage mounted to reciprocate on said frame, a work-carrying spindle rotatably mounted on said carriage, a segment in fixed relation to said spindle during the operation of said tool, a shoe member, a plurality of tapes connected to said shoe member at opposite sides of said spindle and arranged to wind on and yunwind from said segment, power means 4connected to Said spindle for oscillating it, and means for adjustably supporting said shoe member [on said frame, whereby it may be moved in a plane parallel to the movement of said carriage.

1G. Inapparatus of the class described, the combinationof aframe, a tool on the frame, a carriagemounted to reciprocate on said frame, a workscarrying spindle rotatably mounted on Asaifdcarriage, a segment in fixed relation to said spindle during the operation of said tool, al shoe member, a plurality of tapes connected tojsjaid shoe member at opposite sides of said s'pindle and arranged to wind on and unwind' from said segment, power means connected to said spindle for oscillating it, and means for adjustably supporting said shoe member on said vframe, whereby it may be moved in a planepparallel to the movement of said carriage, -the supporting means for said shoev member being adjustable vertically. l, f

17. In apparatus of theelass described, the combination of a frame,a carriage mountedy to reciprocate on the frame, a segment mounted to oscillate on the carriage,;a shoe member, a plurality of tapes connected to said shoe member at opposite sides of said segment and arranged to Wind on and unwind therefrom, power means to oscillate said segment', and means for adjustablysupporting said shoe member on said frame whereby it maybe moved relatively to the axis of said segment. V

18. In apparatus of the class described, the combination of a frame, a tool on the frame, a carriage mounted to reciprocate onV v. said frame, a work-carrying spindle rotatably mounted on'said carriage, a segmentin fixed relation to said spindle during lthe operation ot' said tool, a shoe member, a` plurality-of tapes connected to said shoe member at opposite sides of said spindle and arranged to wind on and unwind from saidv segment,

power means connected to said spindle for oscillating it, means for adjustablysupporting said shoe member on said frame, whereby it may be moved in a plane parallel to the movement of' said carriage, and means for indexing said spindle.

1S). In apparatus ot' the class described, the cembination with a frame, ot' a. slide mounted thereon, a work-barrying spindle on the slide, atool. a tool spindle, means for operating said work carrying spindle and slide to impart to the work carried b'y said spindle-a generating motion relative to the said tool, a support for said tool spindle comprising a hollow arm, a tubular member, within which said tool spindle is supported, slidably' fitting said hollow arm, driving means connected to the spindle intermediate the ends of said 

